Μοντελοποίηση υβριδικής λειτουργίας ηλιοθερμικού σταθμού παραγωγής ηλεκτρικής ενέργειας

Μεταπτυχιακή Διατριβή που υποβλίθηκε στην σχολή ΗΜΜΥ του Πολυτεχνείου Κρήτης για την πλήρωση προϋποθέσεων λήψης του Μεταπτυχιακού Διπλώματος ΕιδίκευσηςSummarization: Concentrated Solar Power (CSP) plants are Renewable Energy Source (RES) units that gain popularity in countries with high solar radiation. CSP plants have already been installed in countries of South Europe and in the Middle East and North Africa, where relevant regulating environment has been developed. The key elements of such legislative frameworks are reviewed in this thesis. Solar dish-Stirling technology is CSP technology that can be more easily integrated into Distribution networks due to its small size. However, a disadvantage of this technology is that features shorter thermal inertia and thus, its output is more volatile compared to large scale CSP plants. In this thesis, the injection to the grid of a solar dish-Stirling plant connected to a battery bank forming a Hybrid plant is studied, in order to determine up to what extent the production volatility and ‘duck curve’ reduction can be achieved. A modeling approach of the electricity output of a solar dish system combined with a lithium-ion battery, is developed. A methodology based on the minimization of the mean square error between the actual and the proposed stabilized production is presented, in order to optimally size the battery bank and reduce the power production volatility of the CSP. Also a methodology is developed to tackle with the ‘duck curve’ effect in providing capacity of 15% and 30% of the nominal power two hours after sunset. Results from the operation of such a Hybrid plant for typical days of various seasons on the island of Crete prove the capability of such a configuration to provide guaranteed amount of power, along with the addition of volatility decrease and capacity credit. To foster such an operation, the principles for suggesting a new premium Feed-in Tariff system to aid the remuneration of power production at various amount of capacity credit providing 2 hours after sunset are suggested. Such a scheme takes into account the battery capacity of the Hybrid CSP, the capacity credit provided and also has a relative dependence of the fuel price used by the most expensive conventional unit. The suggested FiT acts as an additional premium remuneration alongside the remuneration for power production, to the producers that provide capacity credit to the grid, justified also by the economic benefits achieved. The Calculation of these benefits is based on simulations with actual data from the power grid operation based on optimization algorithm, for both solar-dish CSP operation alone and in Hybrid mode offering capacity credit two hours after sunset. Last but not least, in order for the power grid operator to verify capacity credit assurance and receive information from the Hybrid plant, measuring requirements should be issued. A review of existing regulations on this issue is also made in this thesis